You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
102 lines
4.7 KiB
HTML
102 lines
4.7 KiB
HTML
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
|
|
<html>
|
|
<!-- Copyright (C) 1992-2019 Free Software Foundation, Inc.
|
|
Contributed by Cygnus Support. Written by Julia Menapace, Jim Kingdon,
|
|
and David MacKenzie.
|
|
|
|
Permission is granted to copy, distribute and/or modify this document
|
|
under the terms of the GNU Free Documentation License, Version 1.3 or
|
|
any later version published by the Free Software Foundation; with no
|
|
Invariant Sections, with no Front-Cover Texts, and with no Back-Cover
|
|
Texts. A copy of the license is included in the section entitled "GNU
|
|
Free Documentation License". -->
|
|
<!-- Created by GNU Texinfo 6.4, http://www.gnu.org/software/texinfo/ -->
|
|
<head>
|
|
<title>Questions (STABS)</title>
|
|
|
|
<meta name="description" content="Questions (STABS)">
|
|
<meta name="keywords" content="Questions (STABS)">
|
|
<meta name="resource-type" content="document">
|
|
<meta name="distribution" content="global">
|
|
<meta name="Generator" content="makeinfo">
|
|
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
|
|
<link href="index.html#Top" rel="start" title="Top">
|
|
<link href="Symbol-Types-Index.html#Symbol-Types-Index" rel="index" title="Symbol Types Index">
|
|
<link href="index.html#SEC_Contents" rel="contents" title="Table of Contents">
|
|
<link href="index.html#Top" rel="up" title="Top">
|
|
<link href="Stab-Sections.html#Stab-Sections" rel="next" title="Stab Sections">
|
|
<link href="N_005fLENG.html#N_005fLENG" rel="prev" title="N_LENG">
|
|
<style type="text/css">
|
|
<!--
|
|
a.summary-letter {text-decoration: none}
|
|
blockquote.indentedblock {margin-right: 0em}
|
|
blockquote.smallindentedblock {margin-right: 0em; font-size: smaller}
|
|
blockquote.smallquotation {font-size: smaller}
|
|
div.display {margin-left: 3.2em}
|
|
div.example {margin-left: 3.2em}
|
|
div.lisp {margin-left: 3.2em}
|
|
div.smalldisplay {margin-left: 3.2em}
|
|
div.smallexample {margin-left: 3.2em}
|
|
div.smalllisp {margin-left: 3.2em}
|
|
kbd {font-style: oblique}
|
|
pre.display {font-family: inherit}
|
|
pre.format {font-family: inherit}
|
|
pre.menu-comment {font-family: serif}
|
|
pre.menu-preformatted {font-family: serif}
|
|
pre.smalldisplay {font-family: inherit; font-size: smaller}
|
|
pre.smallexample {font-size: smaller}
|
|
pre.smallformat {font-family: inherit; font-size: smaller}
|
|
pre.smalllisp {font-size: smaller}
|
|
span.nolinebreak {white-space: nowrap}
|
|
span.roman {font-family: initial; font-weight: normal}
|
|
span.sansserif {font-family: sans-serif; font-weight: normal}
|
|
ul.no-bullet {list-style: none}
|
|
-->
|
|
</style>
|
|
|
|
|
|
</head>
|
|
|
|
<body lang="en">
|
|
<a name="Questions"></a>
|
|
<div class="header">
|
|
<p>
|
|
Next: <a href="Stab-Sections.html#Stab-Sections" accesskey="n" rel="next">Stab Sections</a>, Previous: <a href="Expanded-Reference.html#Expanded-Reference" accesskey="p" rel="prev">Expanded Reference</a>, Up: <a href="index.html#Top" accesskey="u" rel="up">Top</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Symbol-Types-Index.html#Symbol-Types-Index" title="Index" rel="index">Index</a>]</p>
|
|
</div>
|
|
<hr>
|
|
<a name="Questions-and-Anomalies"></a>
|
|
<h2 class="appendix">Appendix E Questions and Anomalies</h2>
|
|
|
|
<ul>
|
|
<li> For GNU C stabs defining local and global variables (<code>N_LSYM</code> and
|
|
<code>N_GSYM</code>), the desc field is supposed to contain the source
|
|
line number on which the variable is defined. In reality the desc
|
|
field is always 0. (This behavior is defined in <samp>dbxout.c</samp> and
|
|
putting a line number in desc is controlled by ‘<samp>#ifdef
|
|
WINNING_GDB</samp>’, which defaults to false). GDB supposedly uses this
|
|
information if you say ‘<samp>list <var>var</var></samp>’. In reality, <var>var</var> can
|
|
be a variable defined in the program and GDB says ‘<samp>function
|
|
<var>var</var> not defined</samp>’.
|
|
|
|
</li><li> In GNU C stabs, there seems to be no way to differentiate tag types:
|
|
structures, unions, and enums (symbol descriptor ‘<samp>T</samp>’) and typedefs
|
|
(symbol descriptor ‘<samp>t</samp>’) defined at file scope from types defined locally
|
|
to a procedure or other more local scope. They all use the <code>N_LSYM</code>
|
|
stab type. Types defined at procedure scope are emitted after the
|
|
<code>N_RBRAC</code> of the preceding function and before the code of the
|
|
procedure in which they are defined. This is exactly the same as
|
|
types defined in the source file between the two procedure bodies.
|
|
GDB over-compensates by placing all types in block #1, the block for
|
|
symbols of file scope. This is true for default, ‘<samp>-ansi</samp>’ and
|
|
‘<samp>-traditional</samp>’ compiler options. (Bugs gcc/1063, gdb/1066.)
|
|
|
|
</li><li> What ends the procedure scope? Is it the proc block’s <code>N_RBRAC</code> or the
|
|
next <code>N_FUN</code>? (I believe its the first.)
|
|
</li></ul>
|
|
|
|
|
|
|
|
|
|
</body>
|
|
</html>
|